Perplexed by the U.S. economy? You're not alone. Law professor Michael Greenberger joins Fresh Air to explain the sub-prime mortgage crisis, credit defaults, the shaky future of other types of loans and what we can expect from the U.S. financial markets.

Greenberger is a professor at the University of Maryland School of Law and the director of the University's Center for Health and Homeland Security.

Really good explanation of OTC derivatives' contribution to the current economic crisis.